Methods and apparatus for making wire type ultrasonic delay lines

ABSTRACT

METHODS AND APPARATUS FOR ASSEMBLING ULTRASONIC DELAY LINES OF THE TYPE WHEREIN A WIER TRANSMISSION MEDIUM IS COILED UPON A PLURALITY OF SUPPORTING BLOCKS ARE PROVIDED IN ACCORDANCE WITH THE TEACHINGS OF THE INSTANT INVENTION. THE PLURALITY OF SUPPORTING BLOCKS ARE DISPOSED AT SUITABLE INTERVALS ALONG THE COILED TRANSMISSION WIRE AND A PLURALITY OF SLOTS ARE PROVIDED IN EACH SUPPORT BLOCK FOR ACCEPTING INDIVIDUAL PORTIONS OF THE TRANSMISSION WIRE. IN ADDITION, EACH OF THE PLURALITY OF SUPPORTING BLOCKS IS FORMED SO THAT IT IS MOVABLE IN THE RADIAL DIRECTION OF THE COILED TRANSMISSION WIRE. AFTER THE TRANSMISSION WIRE HAS BEEN WOUND UPON THE SUPPORT   BLOCKS, EACH SUPPORT POINT WITHIN A GIVEN SUPPORTING BLOCK MAY BE ADJUSTED IN A SINGLE STROKE FOR OPTIMUM PLACEMENT OF THE INDIVIDUAL PORTIONS OF THE TRANSMISSION WIRE WITHIN THEIR ASSOCIATED SLOTS BY DISPLACING THE SUPPORTING BLOCK A PREDETERMINED AMOUNT IN THE RADIAL DIRECTION OF THE COILED TRANSMISSION WIRE. EACH SUPPORT POINT ASSOCIATED WITH A GIVEN SUPPORTING BLOCK WILL REQUIRE SUBSTANTIALLY THE SAME ADJUSTMENT DUE TO THE INEQUALITY EXISTING BETWEEN THE NATURAL RADIUS OF CURVATURE OF THE TRANSMISSION WIRE AND THE WINDING RADIUS OF CURVATURE RELIED UPON.

United States Patent Inventors Appl. No.

Filed Patented Assignee Priority Kunio Sawada;

Yuzo Matsuda; Hiroshi Kuwabara, Tokyo, Japan Nov. 25, 1968 June 28, 1971 Nippon Electric Company, Limited Tokyo, Japan Dec. 3, 1967 Japan METHODS AND APPARATUS FOR. MAKING WIRE TYPE ULTRASONIC DELAY LINES Primary Examiner-Herman Karl Saalbach Assistant Examiner-Saxfield Chatmon, Jr. Attorney- Mam and J an garathis ABSTRACT: Methods and apparatus for assembling ultrasonic delay lines of the type wherein a wire transmission medium is coiled upon a plurality of supporting blocks are provided in accordance with the teachings of the instant invention. The plurality of supporting blocks are disposed at suitable intervals along the coiled transmission wire and a plurality of slots are provided in each support block for accepting individual portions of the transmission wire. In addition, each of the plurality of supporting blocks is formed so that it is movable in the radial direction of the coiled transmission wire After the transmission wire has been wound upon the support blocks, each support point within a given supporting block may be adjusted in a single stroke for optimum placement of the individual portions of the transmission wire within their associated slots by displacing the supporting block a predetermined amount in the radial direction of the coiled transmission wire. Each support point associated with a given supporting block will require substantially the same adjustment due to the inequality existing between the natural radius of curvature of the transmission wire and the winding radius of curvature relied upon.

Patented June 28, 1971 2 Sheets-Sheet 3 EB EBB EBB S RM 00 T W W0 5 .w n u K Ygzo Motsudu HHOShI Kuwuboro 772mm &

ATTORNEYS METHODS AND APPARATUS FOR MAKING WIRE TYPE ULTRASONIC DELAY LINES This invention relates to assembly techniques and apparatus employed with wire type ultrasonic delay lines and more par ticularly to improvements in methods for adjusting support points of coiled wire type ultrasonic delay lines the apparatus therefor.

Wire type ultrasonic delay lines that are used as internal memories for various electronic devices generally consist of an elongated medium, such as a transmission wire, used for the propagation of ultrasonic energy therethrough. The elongated medium is coiled in the form of multilayer spirals or helices so that the resulting structure is relatively compact and not extremely large in size. The coiled transmission wire is generally supported at a plurality of locations thereon by a plurality of support members or blocks which may be formed; of an elastic material such as rubber, polyethylene, or Teflon. Each of said plurality of support members or blocks is rigidly mounted to the base of easing relied upon to enclose the delay line under fabrication and each support member or block includes a plurality of slots which are each adapted to receive a singular portion of the coiled transmission wire so as to separate as well as support at the support points defined thereby the various turns of the coiled ultrasonic delay line formed. In addition, the transmission wire is provided with transducer means at each end portion thereof so that electrical signals applied thereto may be converted into ultrasonic energy capable of propagating through such ultrasonic delay line and thereafter such ultrasonic energy may be recovered therefrom in the form of electrical signals. Alternatively, one end of the transmission wire may be provided with an input/output transducer means while a second end thereof is provided with a reflective termination.

in the design of such ultrasonic delay lines, the delay exhibited will be a function of the propagation time of the elongated medium relied upon and the length of transmission wire selected. Thus as propagation times of most desirable materials are not greatly variable, where large delay times are desired, it is necessary to rely upon rather substantial lengths of transmission wire. However, since increasing the length of transmission wire; results in an increase in the number of support points and hence in an increase in the amount of absorption of ultrasonic energy by the supporting blocks through such, and support points; it will be appreciated that ultrasonic delay lines will also exhibit large insertion losses principally due to an increase in the propagation loss of the ultrasonic delay line and consequent decrease in the output voltage of the output transducer. Thus where large delay times are desired in ultrasonic delay lines, the degradation of the signalto-noise ratio of said ultrasonic delay line at the output due to the introduction of nondelay induction noise from the input becomes unavoidable together with other undesirable effects.

If the propagation losses due to the absorption of ultrasonic energy by the support blocks in an ultrasonic delay line are considered, it will be manifest to those of ordinary skill in the art, that if each singular portion of the transmission wire relied upon therein merely rests at the bottom of the slot provided therefor in a given support block, the absorption of ultrasonic energy by said support block will be relatively low. However, should the singular portion of the transmission wire present in a given slot exert substantial pressure on the sides of said slot, the amount of ultrasonic energy absorbed by the support block will be significantly increased thereby increasing the propagation losses of the ultrasonic delay line formed and hence decreasing the magnitude of the output signals available therefrom.

An analysis of the propagation losses in ultrasonic delay lines resulting from the absorption of ultrasonic energy at the support points thereof has indicated that regardless of whether the coiled transmission wire; is wound as multilayer spirals or multilayer helices, i.e., the wind methods most prevalently utilized; the coiled transmission wire will exert substantial pressure on the sides of the support slots provided therefor and hence the resulting ultrasonic delay line will exhibit substantial propagation losses under all conditions where the winding radius of curvature R of the coiled transmission wire does not equal the natural radius of curvature R,, of the transmission wire utilized. However; the natural radius of curvature Rn of the transmission wire is detennined by factors such as the drawing process utilized, kind of heat treatment relied upon, as well as many other factors well known to those of ordinary skill in the art; while the winding radius of curvature R is detennined by the delay line design; as a rule, the Rn will not equal the winding radius ofcurvature R relied upon in the fabrication of the ultrasonic delay lines. Therefore, unless the placement of the individual transmission wire portions are adjusted within the slots to thereby ensure that each of the natural radius of curvature support points are suitably positioned, the transmission wire will exert substantial pressure on the slot walls at each support point and hence the resulting ultrasonic delay line will exhibit large propagation losses due to the absorption of ultrasonic energy at the support points by the support blocks 6. The magnitude of the propagation loss exhibited by an ultrasonic delay line will be determined by the magnitude of the inequality of the relationship between the natural radius of curvature R, and the winding radius of curvature R. However, the propagation loss and the attendant decrease in the output voltage will be further accentuated with an increase in the number of support points and hence, with an increase in delay time or the length of the transmission wire. Thus, where rather large delay times are desired the appropriate adjustment of the transmission wire at each support point becomes of paramount importance.

As will be obvious to those of ordinary skill in the art from the above, optimum conditions for an assembled ultrasonic delay line will be realized when the transmission wire is coiled through each of the slots provided therefor in the support blocks at the middle position of the bottom surface thereof and rests thereat by its own weight so as to minimize the contact surface and hence the absorption of ultrasonic energy by the support block. Since such optimum conditions will not ordinarily obtain when the ultrasonic delay line is initially fabricated, due to the differences as aforesaid between the winding radius of curvature R and the natural radius of curvature R,,, it has been conventional to perfonn an adjustment as to the position of the coiled transmission wire in each slot. This adjustment is ordinarily accomplished by; visually inspecting each support point and manually pushing or pulling the wire threaded therethrough in the longitudinal direction until acceptable positioning within the slot is obtained. However, according to this conventional method, not only was every support point required to be checked and adjusted but also whether or not any points that have been previously adjusted are disordered by subsequent adjustments of other support points must be checked while such other support points are being adjusted. The tedious, painstaking, and time-consuming effort required by the foregoing conventional method of optimizing the supporting conditions in an ultrasonic delay line may be readily appreciated by a consideration of an exemplary case. For instance, if an ultrasonic delay line designed to exhibit a 20 millisecond delay is considered, a transmission wire having a length of 60 meters will be required even if a delay line operating in a torsional mode is used. Then, assuming that the winding diameter is mm., the number of turns of coil will be approximately 75. Accordingly, if eight supporting blocks are used, the number of support points which must be checked according to the conventional techniques for optimizing the conditions at each support point mentioned above, becomes as large as 600. Thus it will be appreciated that conventional techniques for optimizing the position of the transmission wire utilized in ultrasonic delay lines at each support point is not only laborious and exceedingly time consuming but will also produce a winding configuration which tends to become uneven and hence is highly inefficient.

Therefore it is a principal object of this invention is to provide methods and apparatus for easily and quickly adjusting the support points of coiled transmission wires such as those present in wire type ultrasonic delay lines.

Another object of this invention is to provide methods and apparatus for making ultrasonic delaylines'which reduce the product cost and at the same time improve thereof.

Other objects and advantages of this'invention will become clear from the following detailed description of an exemplary embodiment thereof and the novel features will be particularly pointed out in conjunction with the appended claims. In accordance with this invention methods and apparatus for the assembly of ultrasonic delay lines are provided wherein, a plurality of blocks for supporting a coiled transmission wire are provided and disposed at suitable intervals along the coiled transmission wire in a manner such that each block may, be moved in the radial direction of winding, support points for the coiled transmission wire are provided at the bottom surfaces of slots in each supporting block and each support point within a given support block may be adjusted at a single stroke by displacing said support block a predetermined length in the radial direction of the coiled transmission wire by relying upon the difference between the natural radius of curvature of the transmission wire utilized and the winding radius of curvature with which said transmission wire has been wound the final fitted into the slots; and adjustment ofjeach support point in the ultrasonic delay line formed is accomplished by the displacement of some or all of the support blocks, in succession in any convenient order, by suitable amounts and clamping the blocks as required.

The invention may best be understood by reference to the following description of an exemplary embodiment thereof in connection with the accompanying drawings, wherein:

FIG. I shows an assembly drawing of a typical wire type ultrasonic delay line;

FIGS. 2(a) and 2(b) show, respectively, sectionalized supporting blocks in radial cross section to illustrate multilayer spiral and helical winding techniques conventionally employed;

FIGS. 3(a) and 3(b) schematically illustrate two different positions nonnally assumed by transmission wires threaded in slots of the supporting block within an ultrasonic delay line when support points are unadjusted condition, FIG. 3(a) illustrating a case in which the natural radius of curvature Rn of the transmission wire is larger than the winding radius of curvature utilized and FIG. 3(b) illustrating a case in which the converse relationship obtains.

FIG. 4 schematically illustrates the position of a transmission wire within slots of a supporting block under ideal transmission wire placement conditions;

FIG. 5 shows a transmission wire support condition for a conventional wire type ultrasonic line under conditions where adjustment has been imperfectly accomplished;

FIG. 6 illustrates the manner in which a transmission wire may be brought to an optimum support condition according to the principles of the present invention; and

FIG. 7 shows a perspective view of an embodiment of modified supporting block apparatus according to the present invention well as transmission wire positions obtainable by the methods taught herein.

Referring now to the drawings and more particularly to FIG. thereof there is shown an assembly drawing of a typical wire type ultrasonic delay line. As shown in FIG. 1, the ultrasonic delay line comprises transducer means 1 and l and an elongated medium for the propagation of ultrasonic energy 2 such as the transmission wire. The transducer means 1 and 1' may take the form of input and out electroacoustic transducer means which act in the well known manner to transform electrical signals into ultrasonic energy or conversely to transduce ultrasonic energy into electrical signals. An input transducer means I may be coupled to one end of the transmission wire 2 for receiving input electrical signals. transducing such input electrical signals into ultrasonic energy and applying the ultrasonic energy derived therefrom to the transmission wire 2 while an output transducer means 1' (shown by the dashed block) is coupled to a second end of the transmission wire 2 so that ultrasonic energy which has propagated therethrough may be recovered in the form of electrical output signals. Alternately. one end of the transmission wire 2 may have an input/output electroacoustic transducer means I, I connected thereto while the second end of said transmission wire 2 is terminated in a reflective termination so that ultrasonic energy is introduced and removed from the transmission wire 2 at the same point after the propagation thereof down and bacl; through said transmission wire 2.

The transmission wire 2 may take the form of any suitable medium which displays appropriate characteristics and propagation times when ultrasonic energy is applied thereto. To reduce the physical size of the ultrasonic delay line formed, the transmission wire 2 is coiled in the form of multilayer spirals or helices through the supporting blocks 3 by threading individual portions of the transmission wire 2 through individual slots 6 present in each supporting block 3. The sup porting blocks 3 may be made of an elastic material such as rubber, polyethylene, or Teflon and are rigidly mounted on a base 5 of a casing. When it is desired to design ultrasonic delay lines exhibiting substantial delay times, the overall length of the transmission wire 2 must be selected to be large. This results in an increase in the number of support points, as defined by the individual portion of the transmission wire 2 supported by a given slot wall 6, and an attendant increase in the amount of absorption of ultrasonic energy by the supporting blocks 3 through such support points. This increase in the ultrasonic energy absorbed will consequently bring about an increase in the propagation loss and a decrease in the output voltage of the output transducer 1' resulting in a degradation of the signal-to-noise ratio of the ultrasonic delay line formed at the output due to the unavoidable introduction of nondelay induction noise from the input together with other undesirable effects.

An analysis of the manner in which ultrasonic energy is absorbed in an ultrasonic delay line assembled in the foregoing manner will be set forth in detail below in conjunction with FIGS. 2(a) and 2(b) which illustrate in cross section two different winding methods generally adopted for the coiled transmission wire 2. In FIG. 2(a) it will be seen from the winding technique illustrated by the arrows that the transmission wire 2 is fitted into the slots in multilayer spirals while in FIG. 2( b) the wire is fitted into the slots in multilayer helices. In both the winding methods illustrated in FIGS. 2(a) and 2(b), the number of support sections may be freely increased by stacking additional supporting block sections vertically using guide pins 4 as indicated in FIG. 2(a), or aligned horizontally as shown in FIG. 2(b) to accommodate any increase in the length of the transmission wire 2 necessary for a proportional increase in the delay time exhibited. In FIGS. 2(a) and 2(b) as well as in all of the other FIGS. relied upon herein, similar reference numerals denote common structure while the letters A and A indicate the outward and inward radial directions, respectively, of the coil formed by the winding of the transmission wire 2.

In an ultrasonic delay line formed in the manner set forth above the transmission wire 2 will exhibit a natural radius of curvature R. which is determined during the manufacture thereof by such factors as the drawing process utilized, the kind of heat treatment relied upon, etc. The winding radius of curvature R is determined by the design of the ultrasonic delay line. As a rule, the natural radius of curvature R, will be unequal to the winding radius of curvature R when the ultrasonic delay line is assembled and unless the support points located in the various supporting blocks 3 are suitably adjusted, the transmission wire 2 will be retained in the slots 6 in a manner illustrated in either FIG. 3(a) or FIG. 3(b) which FIGS. schematically illustrate the two different positions normally assumed by the transmission wire 2 wound in the slots 6 of the supporting block 3 within an ultrasonic delay line. The transmission wire 2 placement conditions illustrated in FIG. 3 depict the conditions which generally obtain at unadjusted support points when the natural radius of curvature R,, of the transmission wire 2 is larger than the winding radius of curvature R, i.e., R,, R, whereby the transmission wire segment at each support point will tend to exert an outwardly directed force in the radial direction A on the walls of slots 6. Similarly. FIG. 3(b) illustrates the conditions which generally obtain at unadjusted support points when the natural radius of curvature R, is smaller than the winding radius of curvature R, i.e., R, R, whereby the transmission wire segment at each support point will lend to exert an inwardly directed force in the radial direction A on the walls of slots 6.

Whenever an inequality exists between the natural radius of curvature R, and the winding radius of curvature R and regardless of which of the winding techniques, as depicted in FIGS. 2(a) and 2(b) are employed, the transmission wire 2 will tend to exert a pressure determined by the relations of R, and R against the outer or inner sidewalls of the slots 6 as shown in FIG. 3(a) and 3(b) which result in an increase in the absorption of ultrasonic energy through the support points, an increase in the propagation loss and a decrease in the output voltage of the ultrasonic delay line. The decrease in the output voltage produced by such an ultrasonic delay line is further accentuated by an increase in the number of support points necessitated by the long transmission wires needed for an increase in the delay time. To relieve the difficulties posed by an inequality between the natural radius of curvature R, of a transmission wire 2 and the winding radius of curvature R relied upon in the assembly of an ultrasonic delay line, it is necessary to adjust the positions of the transmission wire 2 in the slots 6 at each support point so that an optimum condition for the minimum absorption of ultrasonic energy at each support point is approached. As will be apparent to those of ordinary skill in the art, such optimum conditions, as shown in FIG. 4, will obtain when the transmission wire 2 threads each of the slots 6 through the middle portion thereof at the bottom surface of the slot and rests thereat in a manner such that only the weight of the transmission wire portion supported is exerted on the contact surface. Heretofore, the adjustment of conventional wire type ultrasonic delay lines to achieve optimum support point conditions has been extremely difficult because visual and manual methods were relied upon for the adjustment of all of the support points and the actual adjustment of the support points was physically carried out by pushing or pulling the transmission wire 2 in a longitudinal direction. According to this conventional method, not only was it necessary that each and every support point be checked, but also each support point previously adjusted had to be rechecked to insure that subsequent adjustments of other support points did not destroy adjustments previously made. The tedious, painstaking and time consuming effort required by such conventional techniques and apparatus will be readily appreciated by those of ordinary skill in the art as will be the excessive labor costs engendered thereby. Furthermore, use of conventional assembly and support point adjustment apparatus and techniques tends to result in imperfect adjustment of the position of the transmission wire 2 at each support point so that the conditions actually achieved at all of the support points in a given supporting block 6 are not optimized but tend toward the uneven configuration shown in FIG. 5.

Referring now to FIG. 6, it will be seen that the sectionalized supporting block 3 may be adjusted in accordance with the teachings of this invention to be movable in either radial direction A or A of the coiled transmission wire 2 by mounting said sectionalized supporting block 3 on a slotted baseplate 4 and providing means for fixing the position of the slotted baseplate 4 on the casing base 5 after a desired loca tion for the slotted baseplate 4 and hence the supporting block 3 has been achieved. An embodiment of the support block apparatus according to the present invention will be further described in conjunction with FIG. 7 however, at this point in the present description of the instant invention, it is only necessary to note that the supporting block apparatus illustrated In FIG. 6 is movable in either radial direction A or A of the coiled transmission wire and that a plurality of supporting block configurations such as those shown in FIG. 6 may have a transmission wire 2 wound thereon in the form of multilayer spirals or multilayer helices as discussed above in conjunction with FIGS. 2(a) and 2(b), respectively. When a transmission wire 2 is initially wound on the supporting block apparatus depicted in FIG. 6, it will be appreciated that such transmission wire 2 will be uniformly pressed against the outer or inner sidewalls of the slots 6 in the manner illustrated in FIG. 3(0) or 3(b), with a mechanical force determined by the natural radius of curvature Rn and the winding radius of curvature R, due to the inequality which is normally present therebetween. However, with the supporting block apparatus depicted in FIG. 6 the adjustment for optimum conditions as previously set forth may be finished simply by displacing some or all of the blocks in the radial direction outwardly (in the direction A for Rn R) or inwardly (in the direction A for Rn R) by an amount approximately equal to W-d/2, where W slot width and d wire diameter. Thus, with the supporting block apparatus shown in FIG. 6, the adjustment for optimized conditions, as shown in FIG. 4 may be easily and quickly accomplished without requiring any particular skill while undesirable variations in characteristics of the ultrasonic delay lines formed are minimized due to the uniformity of the adjustment technique and the output voltage thereof will not exhibit large insertion losses.

A perspective view of an embodiment of modified supporting block apparatus according to the present invention is shown in FIG. 7. As illustrated in FIG. 7, the supporting block apparatus comprises a sectionalized support block 3 rigidly mounted on a slotted baseplate 4 and the resulting structure is mounted on the casing 5 so as to be movable in either radial direction A or A thereon 'and upon the attainment of a desired adjustment position, the plate 4 may be securely clamped in such position by the mounting means shown in association with the slotted baseplate 4. When the movable supporting block apparatus according to this invention is relied upon in the assembly of an ultrasonic delay line, as shown in FIG. I, the suitable displacement of some or all of the supporting blocks outwardly (direction A) or inwardly (direction A) in any desired order may be relied upon to achieve the adjustment of each support point for optimum conditions in a straight forward and expeditious manner. Furthermore, as each point in the sectionalized support block 3 is adjusted at the same time and the inequality between the natural radius of curvature R and the winding radius of curvature R is relied upon; it will be realized that optimized support conditions as shown in FIGS. 4, 6 and 7 may be quickly and easily attained. For instance, if a torsional mode wire type ultrasonic delay line having delay time of 20 milliseconds is considered, the advantages of the instant invention are immediately rendered manifest. The torsional mode of operation is inherently void of dispersion and hence is normally used as the vibration mode for delay lines whose delay times are of the order of milliseconds. As has been publicly known, the amount of dispersion due to the radius of curvature of a coiled transmission wire is inversely proportional to the product of the winding radius of curvature Rn and the natural radius of curvature R and therefore, Rn must be designed to be as large as possible to minimize the dispersion. Under the coil supporting state shown in FIG. 2(a), the ultrasonic energy propagating along the transmission wire 2 will be almost means 1' absorbed by the supporting blocks 3 and the output voltage from the output electroacoustic transducer means 1 will be very substantially attenuated. However, if the supporting block apparatus utilized is designed to be adjustable in the radial direction as shown in the embodiment of this invention illustrated in FIG. 7, some or all of the supporting blocks 3 may be displaced outwardly in the radial direction A or inwardly in the radial direction A in any desired order to easily and quickly achieve the ideal state as shown in FIG. 4 at each support point. Thus, an experimental survey conducted to determine the contribution provided by the instant invention has demonstrated that the overall fabrication time of a wire type ultrasonic delay line exhibiting a millisecond delay and fonned using the apparatus and methods taught by this invention was one-third of that required using conventional techniques while, the output voltage obtained from ultrasonic delay lines formed according to the teachings herein were doubled and variations in the characteristics of the ultrasonic delay lines formed were markedly decreased.

It will be obvious from the foregoing description that the merits of this invention are applicable to various forms of wire type ultrasonic delay lines and especially to wire type ultrasonic delay lines using torsional modes of vibration having inherently large delay times because the instant invention acts in contributing to a marked reduction in the manufacturing costs and at the same time enables the production of ultrasonic delay lines having substantially increased output voltages.

While the principles of this invention have been described in connection with a particular embodiment thereof. as applied to particular wire supporting systems, it is to be clearly understood that the scope of this invention comprises any equivalent method and means applicable to other supporting systems adopted for wire type ultrasonic delay lines. Accordingly, the devices. apparatus, or tools built for incorporation into or removal, after adjustment, from the delay lines are considered to reside within the scope of this invention and thus the invention is deemed to be limited solely by the claims and the equivalents thereof.

We claim: l. A method of making a wire type ultrasonic delay line comprising the steps of:

winding a transmission wire suitable for propagating ultrasonic energy therethrough upon a plurality of supporting block means to form a coil each of said supporting block means being movable in the radial direction of said coil formed by said winding of said transmission wire and including a plurality of slots adapted to accept individual portions of said transmission wire, said transmission wire being wound upon said plurality of supporting block means in a manner such that individual portions of said transmission wire are present in selected ones of said plurality of slots and supported thereby; inspecting the manner in which said individual portions of said transmission wire are supported within the slots of selected ones of said plurality of supporting block means; and

displacing at least one of said plurality of supporting block means in the radial direction of said coil of transmission wire until desired ones of said individual portions of said transmission wire are supported in said slots of said one supporting block means in a manner such that said desired ones of said individual portions of said transmission wire are supported substantially by only one surface of the slots associated therewith.

2. The method of making a wire type ultrasonic delay line according to claim 1 additionally comprising the step of fixing the position of said at least one of said plurality of supporting block means in the position achieved by said step of displacing by securing said displaced supporting block to a base upon which said ultrasonic delay line is formed.

3. The method of making a wire type ultrasonic delay line according to claim 2 additionally comprising the step of winding said transmission wire through said plurality of slots in said plurality of supporting block means in the form of multilayer spirals.

4. The method of making a wire type ultrasonic delay line according to claim 2 additionally comprising the step of winding said transmission wire through said plurality of slots in said plurality of supporting block means in the form of multilayer helices.

5. Apparatus for supporting a coiled transmission wire of an ultrasonic delay line, said apparatus comprising:

support bloc means taking the form of a so id member having a plurality of slots therein, each of said plurality of slots being adapted to accept individual portions of said transmission wire;

adjustable positioning means for establishing said support block means in a position which is substantially transverse to an axis of each of said plurality of slots therein, said adjustable positioning means including means for selectively enabling said support block means to be displaced in a direction common to a radial line of said coiled transmission wire to selectively vary the position of said individual portions of said transmission wire accepted by associated slots within said support block means; and

means for rigidly mounting said support block means to casing means upon which said ultrasonic delay line is formed.

6. The apparatus for supporting a coiled transmission wire of an ultrasonic delay line according to claim 7 wherein said adjustable positioning means for establishing said support block means in a position which is substantially transverse to an axis of each of said plurality of slots comprises a slotted blseplate rigidly mounted to a lower surface of said support block means.

7. The apparatus for supporting a coiled transmission wire of an ultrasonic delay line according to claim 5 wherein said means for rigidly mounting said support block means comprises mounting means inserted tlu'ough slotted portions of said baseplate means into said casing means.

8. An ultrasonic delay line comprising:

casing means adapted to have an ultrasonic delay line formed thereon;

a plurality of supporting block means, each of said supporting block means including a plurality of slots therein;

a transmission wire wound in the form of a coil on said plurality of said supporting block means, said, transmission wire being wound through said plurality of slots in said plurality of supporting block means in a manner such that individual portions thereof are wound through selected ones of said plurality of slots and supported thereby;

electroacoustic transducer means connected to said transmission wire, said electroacoustic transducer means acting upon the receipt of electrical input signals to apply ultrasonic energy representative of said input signals to said transmission wire and conversely to produce electrical output signals upon the receipt of ultrasonic energy from said transmission wire; and

means for adjustably mounting each of said plurality of supporting block means to said casing means, said adjustable mounting means allowing each of said plurality of supporting block means to be selectively displaced in a radial direction of said coil formed of said transmission wire so that the position of said individual portions of said transmission wire within respective slots of said plurality of supporting block means may be selectively varied.

9. The ultrasonic delay line according to claim 8 wherein said adjustable mounting means comprises a plurality of slotted plate means, each of said plurality of slotted plate means being rigidly affixed to an associated one of said plurality of supporting block means and adjustable fastener means inserted through slotted portions of each of said plurality of slotted plate means into said casing means.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent 1.588J55 .lunsi l8 l2l1 Inventor(s) Kunio Sawada Yuzo Matsuda, and Hiroshi Kuwabara It is certified that error appears in the above-identified patent and that said Letters Patent are hereby correcced as shown below:

Column 8, line 23, "claim 7" should be --claim 5--.

Signed and sealed this 7th day of March 1972.

'(sEAL) Atbest:

EDWARD M.FLJ:;TCHBR,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents USCOMM'DC 60376-P69 FORM 5 0-1050 (10-69) 9 DJ. GOVIRNNINY PRINTING OI'HCI: I!" O-llldll 

